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Toilet of the future is flush with solar power, sensors

How do you build the toilet of the future, and one that can be used in developing countries where sanitation can be lacking?

About 2.5 billion people in the world live without basic sanitation, including toilets, resulting in a child dying about every 20 seconds, according to the U.N. World Water Development Report.

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Clearly more toilets are needed. Here’s how researchers at the California Institute of Technology have been going about it, in seven high-tech steps.

1. Patent a design for “multilayered nanostructures doing electrochemical degradation,” which is exactly what Caltech environmental professor Michael Hoffmann did 20 years ago.

2. Employ the patent to design a system using a solar panel and battery to power an electrochemical reaction (sort an anaerobic digester) that breaks down solids into fertilizer and sanitizes the water to be reused for flushing or irrigation. Caltech says hydrogen for fuel pumps can also be produced.

3. Win the Bill and Melinda Gates Foundation’s Reinvent the Toilet Challenge in 2012 with the high-tech toilet design and receive a $400,000 grant.

4. Add sensors to monitor leaks, water clarity, particulates in the water, pressure, and voltage. This makes repair easy, because let’s face it: Poop happens and stuff happens where poop happens. Alerts are sent to an operator who gets a picture of exactly where the problem is, and what needs to be done. In a Fast Company article, Caltech engineers say this will reduce operating costs.

5. Sign on toilet innovator Kohler to provide plumbing parts and expertise.

Toilet of Future app
Image used with permission by copyright holder

6. Have trials of the toilets in a full bathroom treatment at Mahatma Gandhi University in India, pair it with Eram Scientific‘s self-cleaning “eToilet” in Northern India, and work with Chinese government on developing a toilet houses in shipping container to send to schools in South Africa.

7. Have as many people as possible use the toilets. Although the Chinese design may cost $15,000, a Caltech researcher says this meets the Gates Foundation’s original target of sanitation for five cents per person per day.

Happy flushing!

Self-Contained, PV-Powered Domestic Toilet & Wastewater Treatment System
Steve Castle
Former Digital Trends Contributor
Steve Castle’s fascination with technology began as a staff writer for luxury magazine Robb Report, where he reported on…
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